


That Old Slippery Slope

by Lenore



Series: That Old Slippery Slope [1]
Category: Supernatural
Genre: Genderswap, Plot What Plot, Porn, Sibling Incest
Language: English
Status: Completed
Published: 2011-08-17
Updated: 2011-08-17
Packaged: 2017-10-22 18:27:15
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,340
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/241177
Author URL: https://archiveofourown.org/users/Lenore/pseuds/Lenore
Summary: <blockquote class="userstuff">
              <p>Shameless Sam/girl!Dean porn</p>
            </blockquote>





	That Old Slippery Slope

The problem with Dean waking up a girl was not so much that Sam was curious about his new body—or should he say her new body? pronouns had become a challenge—but that Dean himself had an explorer's spirit about it.

At lunch, he kept looking down his own shirt, much to Sam's dismay, asking in a too-loud voice, "I'm probably like a C-cup, don't you think?"

In the car, he took the opportunity at every stoplight to feel himself up. "Nice and round. Seriously, man. I've got a great set of boobs over here."

When Sam offered to take over the driving so Dean wouldn't have to bother with little things like keeping his eye on the road, Dean just scowled at him.

"Is that a crack about women drivers? 'Cause I thought those Stanford chicks would have beaten the chauvinism out of you already."

It only got worse when they called it a night and went back to the motel, no luck hunting down whatever had put the whammy on Dean. The door had barely clicked closed when off came Dean's shirt.

"What—" Sam stuttered, "what you do think you're doing?"

Dean gave him an incredulous look. "Dude, boobs I can touch without getting my hand smacked. I'm not letting that go to waste."

He cupped his breasts in his hands, staring down at himself, a disturbing leer on his feminine features.

"God. Stop doing that!" Sam shouted.

Dean just smiled, rubbing his thumb in slow circles. "Why? You jealous or something?"

"You are insane." He stomped over to the dresser and started shoving stuff heedlessly into it, as if tidying the room were the most important thing ever, thumping the drawers more loudly than was strictly necessary.

"Come on," Dean said in a wheedling voice, all the more grating now that it was a high-pitched wheedle. "You want to touch them. I know you do."

Sam snapped his head around to glare. " _I'm_ not a pervert."

Dean lifted one, delicate eyebrow. "Sure you are. You're a guy."

Sam dumped the change out of his pocket and pretended to be utterly engrossed in counting it. It didn't matter what Dean did, Sam was just going to ignore him. Going to ignore him. Going to—he let out a sigh. Dean was actually rather hard to ignore when he was groping his own boobs, a thought that alarmed Sam on so many, many levels.

"Come over here and touch them for me. Please?"

Sam's face went instantly hot. "No!"

"I want to know how it feels," Dean said, as if this were a completely reasonable request. "It's not every day that I have boobs."

 _Let's hope not at least,_ Sam thought.

"You're already touching them," he pointed out sensibly. "You don't need me to do it."

"It's different when it's somebody else's hands. Like jerking off. Always feels better when somebody else does it." Dean gave him a fluttery look, all eyelashes and pretty please, and Sam could feel the proverbial slippery slope shifting beneath his feet.

"If I do this, that's it, that's all, the end of it."

Dean's pretty mouth curved into a smile. "Sure. Whatever you say, Sammy. Now get over here."

Sam did, and then the problems really set in. Oh, he knew what to do with a pair of willing breasts, a macho voice from some nether region of his brain proudly proclaimed. But his brother's breasts? That was a different matter entirely. He held his hands up, trying to figure an angle of approach.

"I hope this isn't your usual technique," Dean said, clearly unimpressed. "'Cause if it is, it's a miracle you ever got laid."

"Could you be quiet? I'm trying to—"

"Oh, for God's sake, Sam, just—" He grabbed Sam's hands and put them on his breasts. "See? Not rocket science."

"Shit!" was Sam's highly articulate reply.

Dean—well, he was a handful, quite literally, round and firm, skin so soft. Apparently it had been way too long since Sam had had his hands on boobs because it was making him hard, just this, just touching.

"You like them," Dean said triumphantly.

"I am not going to dignify that," Sam said, sounding pissy even to himself.

Dean, never one to let anything go, insisted, "You do. I know you do. You think I'm hot. Just admit it—"

Sam skimmed his thumbs over Dean's nipples, and Dean sucked his breath in through his teeth, one way to shut him up.

Although not for long. "Shit! Do that again."

Sam traced one areola with his finger, then the other. He could feel Dean's breath against his cheek, feel him trembling. Dean's eyes were huge, all pupil, fastened on Sam.

"Please. I want—"

Heat of the moment and all that, and Sam nudged his leg between Dean's thighs. Dean started to rock against him, and then Sam lost all sense, bending his head, pressing a kiss to Dean's soft curves.

"Sammy!" Dean's fingers grappled at his head, holding him there.

Sam kissed wetly around one nipple, then flicked out his tongue. That was it, all it took. Dean lunged against him hard, went perfectly still. For a moment, Sam couldn't even feel him breathing. Then Dean couldn't seem to get enough air, noisily gulping down big lungfuls of it, his body jerking as he climaxed.

"Whoa," he said when it was over, hands still tangled up in Sam's T-shirt. "And girls get multiples ones of those. Damn."

"Can you put your shirt on now?" Sam asked plaintively. That he'd just given his brother-turned-girl an orgasm was at the top of his list of things he really never needed to think about again.

Dean being Dean, though, made no move to get dressed, eyed Sam's hard-on. "You want me to—"

"No!" He yanked the hem of his shirt down as far as it would go.

Dean shrugged. "Whatever, man. Just thought I'd return the favor."

"Let's get some sleep, okay? Tomorrow we can work on getting you back to normal. And forget any of this ever happened."

Dean yawned. "Okay."

He threw back the blankets and bounced into bed. Sam tried not to watch, he really did. With a sigh, he switched off the light. He couldn't remember the last time he'd been so glad for darkness.

* * *

The next morning, they headed over to the diner next door for breakfast, and Sam couldn't shake the feeling that everyone who saw them knew. He kept his head down and mumbled into the menu when the waitress came to take their order.

His brother amused himself standing packets of sugar on end, as if absolutely nothing had happened last night. "You've really got to stop worrying so much," he said, without looking up from his architectural efforts.

"I'm a pervert, Dean. If that's not something to worry about, I don't know what is."

Dean threw up his hands, the sudden air current knocking down his sugar house. "So we're perverts? Who cares?"

"At least you have an excuse, all hopped up on hormones you're not used to."

"That's pretty sexist, dude."

"But _me_. What's my excuse? I just—"

"Helped me out when I asked you to. Like a good brother."

"If some other guy tried that with you, I'd—"

Dean looked interested. "What?"

"Kick him until he was dead," Sam said, with feeling.

Dean grinned. "You're cute when you're over-protective, Sammy."

Sam would have told Dean to fuck off, but he didn't like being rude to girls.

* * *

Maybe if Dean could have kept his "Our Bodies, Our Selves" revelations to himself nothing more would have happened, but when had self-restraint ever been Dean's strong suit?

They spent a fruitless day trying to track down whatever had taken the Y out of Dean's chromosomes, made an excruciatingly long stop at the mall. Regular-Dean had been happy to wear the same rumpled jeans days on end, but girl-Dean had a picky sense of personal style. Finally, they dragged themselves back to the motel, and Dean instantly commandeered the bathroom, locking himself inside, doing who knew what. Sam certainly wasn't going to ask.

Not that this was necessary, of course. After a while the door banged open, and Dean came out and announced, "I'm a virgin."

"I seriously doubt that," Sam told him.

"No, really. I did some exploring. I could feel the—"

"Please," Sam cut him off. "Stop."

"I can't be a virgin, Sam. That's just unnatural."

"Clearly you missed out on abstinence-only sex education."

"I mean it's unnatural for _me_. I haven't been a virgin in—" He waved his hand. "A really long time."

"Well, I don't know what you expect me to do about it."

Dean flashed an insinuating smile, and Sam stared at him like he'd lost his mind along with his dick.

"That's not funny," he told his brother.

"Oh, come on. It's not like this is really _me_. I'm just borrowing this body. It wouldn't be like we're—"

"Yes! That's exactly what it would be like."

Dean crossed his arms over his chest. "You think I'm hot. I know you do."

"Why do you have to be so obsessed with sex?"

"Would it be better if I were throwing a shit fit because I mysteriously woke up with a vagina?" For the first time, Sam could hear the stress of the situation in his voice.

"We'll figure it out," Sam reassured him. "It might just wear off even."

"In the meantime, I'm trying to see this as an opportunity. You're always telling me I could stand to learn a few things about women. So help me out here."

Sam shook his head, no words coming readily to mind to express just how fucked up that brand of logic was.

Dean snorted in disgust. "Fine." He gathered up his shopping bags and slammed the bathroom door behind him.

There was a whole bunch of rustling and thudding in there, and Dean came back out some time later, all girled up in a skirt, stockings, some filmy kind of shirt, heels he was a little wobbly in. He grabbed his wallet and his keys, looked for some place to put them, but there wasn't exactly room for a pocket in a skirt that tight.

"Damn it. I forgot to get a purse."

"What do you think you're doing?" Sam asked.

"Going out."

"Out where?"

"Bar down the street." He smiled that devil-may-care smile of his, and the girl version of it did funny things to Sam. "I ought to be able to find some company there. Real friendly company." He winked.

The thought of some boozy loser pawing at Dean did even funnier things to Sam.

He caught Dean by the arm as he headed for the door. "Don’t."

"Give me a reason not to."

There was no rational thought process that took place, no _if I humor Dean, maybe he'll stop being a stupid ass_. There was just a sudden surge of movement, Dean's body against his, soft and round, a perfect fit, Dean's mouth beneath his, hot and urgent, and the inescapable realization that Sam really could do this.

So of course he pulled away and insisted, "I can't. You're my—"

"No," Dean cut him off. "Pretend I'm somebody else. Just some girl. Wanda or something."

Sam rolled his eyes. "Wanda."

"Work with me here, Sammy."

He wound an arm around Sam's neck and kissed him again. Sam tightened his hold on Dean's waist. Of course there was no pretending he was anyone else, even if Sam had wanted to, not when he still smelled like Dean. But the kisses felt good, and that was just what happened on the slippery slope. You fell.

Dean fumbled with the buttons of his blouse, pulled it impatiently up over his head. Really, if Sam had any presence of mind at all, he would have found it disturbing how much Dean liked to flash his boobs. But then there they were, and that was it for presence of mind. Sam ran his thumb along the edge of one candy-red lace cup. Dean's taste in lingerie was obvious, but exciting. Sam pressed a kiss into the cleft between his breasts, just above the little white bow.

"So you do think I'm hot, huh?" Dean murmured in a sleepy sex voice.

Sam bit him on the collarbone. "You know you're gorgeous."

Dean laughed, giggled really, and Sam sank back onto the edge of the bed, pulled Dean down onto him. Dean squirmed and shifted and settled at last with his ass pressed flush against Sam's dick.

"I wonder if this is what they mean by girl power?" he asked with a smile, doing his best rendition of a lap dance, making Sam, who was already hard, downright desperate.

Dean might be a girl at the moment, but the brotherly spirit of one-upmanship did not die so easily. He flipped the clasp of Dean's bra with his thumb, tossed it over his head, put his hands and mouth all over Dean's breasts, and got off on his own power to make Dean gasp.

He flipped him over, laid him out on the bed, pushed up his skirt, moved his panties out of the way. Dean was already wet, and he bit his lip when Sam started to touch him.

"Sammy," he said, soft and breathy.

He had his hands on his breasts, rubbing his palms over his nipples. He stared up at Sam, lashes lowered, his expression more and more strained until he squeezed his eyes tightly shut, coming so easily, so prettily that Sam wanted to make him do it some more. A lot more.

He pulled his own shirt off, let it fall to the floor, and stretched out over Dean to kiss him. His chest bare against Dean's, and Dean groaned. "God, that feels good!"

Sam managed to get his hand under Dean, find the zipper on the skirt. Dean obligingly shimmied his hips to help Sam pull it and his stockings off. Sam pressed a kiss to his belly, and Dean smiled.

"You gonna give me the full treatment, Sammy?"

Sam moved lower, mouthing warm flesh through silky red panties. "How often do you wake up with one of these?" He hooked his thumbs in the underwear and slid it off.

"Mmm," Dean moaned and flung his legs open.

Sam often thought how stupid guys were for not wanting to do this, because girls tasted good, and they made hot little noises when you used your tongue on them, like Dean was doing now, and what could possibly be a more manly achievement than making a girl come and come?

"Don't stop!" Dean begged.

And Sam didn't, not for a long time.

When he finally lifted his head, Dean was completely limp-limbed and smiling. "I'll never shortchange a girl on that again, I swear."

Sam laughed and kissed him, and Dean held on, getting a taste of himself in Sam's mouth.

"Now," Dean said, "what can I do for you?"

He gave Sam a speculative look, another kiss, then popped the button on his jeans and put his hand down his pants.

"Fuck!" Sam hissed through his teeth.

Dainty little hand, but nothing dainty about what it was doing. Dean knew what guys liked, firm grip, hard strokes, and God yes! It was so much better when somebody else was doing the touching.

Dean watched him, way too pleased with himself. "You like that, don't you?"

Sam's lip trembled. "Please," in a cracked voice, all he could manage.

But then it just stopped, the hand gone. Dean pushed at his shoulders, and he rolled over, and Dean scrambled up from the bed. Sam put his arm over his eyes, the sound of his own rattled breathing painfully loud in his ears. If there was one thing he would not have guessed about his brother, it was that he'd be a tease.

A second later, though, there was a tug at his jeans, and he jerked his arm away, eyes flying open.

"Come on. You got to help me out here," Dean complained. "For somebody so skinny, you weigh a ton."

Dean had a condom wrapper in his hand, and Sam yanked his jeans and underwear down his legs with one sharp pull, kicked them off the bed.

Still, he felt the need to say, "You don't have to."

Their eyes met, Dean's all bottomless and dark, and Sam's skin felt way too hot.

Dean grinned. "I do if I don't want to stay a virgin the rest of my hopefully short female life."

He rolled the condom onto Sam, years of practice evident, and crawled up his body to lie on top of him. They kissed messily, Sam's fingers in Dean's hair, splayed across his back, cupping his jaw, everywhere he could get them.

"I want you," he admitted at last, just because it seemed the honorable thing to do.

"Duh," Dean said, with a quirk of his eyebrow.

He slid his knees on either side of Sam's hips, braced himself with one hand, took Sam's cock in the other.

"Be careful," Sam told him.

"You realize I'm only sort of a virgin, right?" Dean said, as he started to push down.

"I don't want to hurt you."

It was barely out of his mouth when he breached Dean's body, and Dean's eyes went wide.

"Shit!" Sam's fingers dug into Dean's hips, holding him still.

Dean laughed softly. "If teenaged girls can do this, I think I can." But there were lines of strain showing at the corners of his mouth.

"Just take it slow."

Which, really, Sam thought should secure him a spot in heaven, or at least help dig him out of hell, because Dean was hot and tight and perfect, and taking it slow was the last thing he wanted.

Happily, Dean was no paragon of patience either, and he gritted his teeth and kept pushing until his body yielded at last and Sam was all the way inside.

He was breathing hard, sweat on his face, and Sam rubbed his hands over his thighs. "Okay?"

Dean nodded, inhaled deeply and started to move, slowly at first, then more easily. Sam shifted his hips, and then Dean's mouth flew open. "Oh my God! I thought the g-spot was just some crap they wrote about in women's magazines. But—" Shocked pleasure lit up his face.

Sam smiled and rolled Dean over onto his back, got a better angle, and started to drive at that spot.

"Shit! Shit!" Dean said in a shaky voice.

He wrapped his legs around Sam's waist, holding on tight, and Sam pressed his face against his neck, breathed in his sweat, and thrust into him over and over.

"I could never pretend you were anyone else," he confessed in a whisper.

Dean went rigid beneath him, and Sam felt the sweet clench of his body, and then Sam was babbling nonsense, eyes squeezed closed, just as utterly lost.

Afterwards, he was careful with the condom—because the consequences of not being careful were too horrifying to contemplate—and silently cursed the motel and its lack of wastebaskets. He tied it off and left it in the drawer of the nightstand, figuring that's just what they got for being cheap.

Dean's lips looked tender, and his hair was a mess, sticking out in all directions. Sam put his arm around him. "You okay?"

"Better than okay." He smiled softly. "I bet you were a really good boyfriend, Sammy."

Sam pushed the sweat-dark hair off his forehead and kissed him there. Dean laid his head on Sam's chest, and Sam tightened his arms around him.

"Do you think I'll turn back soon?" Dean murmured against his ribs.

"I hope so," Sam told him.

"Me too," Dean said sleepily.

Sam closed his eyes. Regret hadn't set in yet. He figured that would hit him in the morning. For now, it just felt good to have someone he loved in his arms again.


End file.
